A form factor is the physical size and shape of a device or of a component of a device. A key input form factor is the physical size and shape of a keyboard, for example. As handheld devices, such as cell phones, personal digital assistants (PDA), smart phones, etc., become increasingly popular for mobile communications and mobile data access, key input form factors for handheld devices must meet the physical biomechanics of the human users and must be adapted to accommodate the limited amount of space provided.